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W222 S63 AMG M157 Catless Downpipes – Premium Stainless Steel High-Flow Set
W222 S63 AMG M157 Catless Downpipes – Premium Stainless Steel High-Flow Set
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For the serious W222 S63 owner who wants to unlock the full potential of the M157 BiTurbo V8. These premium stainless steel catless downpipes dramatically reduce exhaust restriction, deliver a deeper and more aggressive AMG exhaust note, and provide noticeable improvements in turbo spool and mid-range response.
What's Included
- Complete left + right catless downpipe set
- Premium V-band clamps and mounting hardware
- Gaskets included
Build It In One Order
Everything the S63 wants alongside the downpipes is in the selector above — no second checkout, no re-flash later.
Add ECU Tune — the downpipes are the hardware half of a Stage 2 M157. The calibration is what turns them loose: it lets the ECU use the extra flow, and it clears the check-engine light the catless design will otherwise set. Bundled here it comes in under the price of buying the tune on its own afterwards.
Add Filters + Intake Spacer Kit — opening the exhaust side moves the restriction upstream. The spacer kit and high-flow filters feed the turbos the air they can now actually use. Fitted in minutes, and the natural companion to a Stage 2 exhaust.
One Small Part Worth Adding
Catless downpipes reposition the O₂ sensor bungs relative to the factory pipe, and the original sensor leads often will not reach comfortably once the new pipes are in.
24″ O₂ sensor extension harness → — avoids stretching or splicing the factory harness. It is the cheapest part in the build and the one most likely to stall an install halfway through a Saturday.
Key Benefits
- Reduced backpressure — faster turbo spool and stronger mid-range power
- Deeper AMG V8 sound — rich crackles and pops when tuned
- Premium 304 stainless steel with back-purged TIG welds for long-term reliability
- True bolt-on fitment — no cutting or modifications required
- Built for serious S63 builds — the flagship AMG sedan deserves flagship hardware
Vehicle Compatibility
| Years | Model | Chassis | Engine |
|---|---|---|---|
| 2014–2017 | Mercedes-AMG S63 | W222 | M157 5.5L BiTurbo V8 |
If your car is on that list, these bolt straight on with no cutting. Not sure? Send us your year and model and we'll confirm before you order
Why S63 Owners Choose These
The W222 S63 is already a flagship grand tourer. These catless downpipes give it the sound, response, and flow the M157 was always capable of — without compromising daily drivability.
Installation
Direct bolt-on replacement. Average install time 2–3 hours; professional installation strongly recommended. Re-check for leaks after the first heat cycle.
Frequently Asked Questions
Will these throw a check engine light?
Likely, on an untuned car. Removing the cats means the downstream O₂ sensors read differently than the ECU expects. A calibration resolves it properly — we do not recommend defeat devices.
What is in the Filters + Intake Spacer Kit option?
High-flow air filters together with the airbox spacer kit for the M157 airbox. It is the intake-side counterpart to the downpipes — the downpipes let the exhaust out, this lets more air in. Sold here as a single add-on so it ships with your downpipes in one order.
Do I need the O₂ sensor extension harness?
Often, yes. A catless downpipe repositions the sensor bungs relative to the factory pipe, and the original leads may not reach comfortably. A 24″ extension avoids stretching or splicing the harness — a small part that prevents a stalled install.
How much power can I expect?
Noticeable gains in mid-range torque and throttle response. Exact figures depend on your calibration and supporting modifications.
Do these require a tune?
The car will run without one, but tuning is strongly recommended for full benefit and to clear fault codes.
Are these street legal?
No. These delete the primary catalytic converter. They hold no CARB Executive Order, are not 50-state legal, and are not legal to install on a vehicle registered or operated on public roads in the United States. Sold for closed-course competition and off-road use only — see the emissions notice at the top of this page.
Is there a warranty?
Yes — a 12-month structural warranty, with guaranteed fitment on every model listed above.
Buy With Confidence
- 12-month structural warranty with guaranteed fitment on listed models
- Free U.S. shipping with tracking on every order
- Fitment confirmed before you buy — send your VIN and we'll verify before you order
- Mercedes-AMG specialists — we focus exclusively on Mercedes platforms and know the M157 inside out
- Real support — questions before or after purchase go straight to us, not a call center
Confirm fitment or ask a question →
Off road use only. Not legal for use on emissions-controlled vehicles or public roads.
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